Healthy men were randomly assigned to one of the two groups: about half were given alcohol to
Question:
Healthy men were randomly assigned to one of the two groups: about half were given alcohol to drink (0.85 grams of per kilogram of body weight); the rest drank a placebo. Participants were then given 30 minutes to read up to 36 pages of a book. Every three to four minutes participants were prompted to indicate whether they were “zoning out” (losing concentration on what they were reading). The number of times participants indicated they were “zoning out” was recorded for each subject. Is there evidence of a difference in the groups in “zoning out”. The following table summarizes data on the number of episodes of zoning out.
Group | n | mean | sd |
Alcohol | 30 | 1.64 | .55 |
Placebo | 25 | 0.14 | .65 |
Use α=.1. Carry out the test.
(a) What is the probability of a Type I Error?
(b) Using symbols set up the appropriate null and alternative hypotheses to test.
(c) Calculate the value of the test statistic (with degrees of freedom if applicable and show work).
(d) Determine the p-value of the test (or the range of the p-value).
(e) Do you reject at the 10% significance level (α = 0.1)? Explain why or why not.
(f) State your conclusion in the context of the claim above.
Introduction to Probability and Statistics
ISBN: 978-1133103752
14th edition
Authors: William Mendenhall, Robert Beaver, Barbara Beaver